Book Image

Mastering Geospatial Analysis with Python

By : Silas Toms, Paul Crickard, Eric van Rees
Book Image

Mastering Geospatial Analysis with Python

By: Silas Toms, Paul Crickard, Eric van Rees

Overview of this book

Python comes with a host of open source libraries and tools that help you work on professional geoprocessing tasks without investing in expensive tools. This book will introduce Python developers, both new and experienced, to a variety of new code libraries that have been developed to perform geospatial analysis, statistical analysis, and data management. This book will use examples and code snippets that will help explain how Python 3 differs from Python 2, and how these new code libraries can be used to solve age-old problems in geospatial analysis. You will begin by understanding what geoprocessing is and explore the tools and libraries that Python 3 offers. You will then learn to use Python code libraries to read and write geospatial data. You will then learn to perform geospatial queries within databases and learn PyQGIS to automate analysis within the QGIS mapping suite. Moving forward, you will explore the newly released ArcGIS API for Python and ArcGIS Online to perform geospatial analysis and create ArcGIS Online web maps. Further, you will deep dive into Python Geospatial web frameworks and learn to create a geospatial REST API.
Table of Contents (23 chapters)
Title Page
Copyright and Credits
Packt Upsell
Geoprocessing with Geodatabases

Raster operations using PostgreSQL

In the first section of this chapter, you were able to load, display, and query rasters using gdal. In this section, you will learn how to load and query rasters using a spatial database—PostgreSQL. As you start to model your data, you will most likely hold it in a spatial database. You can leverage your database to perform the queries on your rasters.

Loading rasters into PostgreSQL

To load a raster into PostgreSQL, you can use the raster2pgsql binary. If it is not in your path, you may need to add it. You should be able to find the binary in your PostgreSQL install directory on Windows at \PostgreSQL\10\bin.

The following command should be executed from your operating system's command line. It will load the TIF you created earlier in this chapter into an existing PostgreSQL database:

>raster2pgsql -I -C -s 4326 C:\Users\Paul\Desktop\BigI.tif public.bigi | psql -U postgres -d pythonspatial

The previous command uses raster2pgsql with the -I (creates an index...